Open Access

ARTICLE

Effects of PBO and PP₃₃₃ on Shoot Growth, Nutrient Accumulation, and Fruit Quality in Carya Illinoinensis cv. ‘Shaoxing’

Yunqi Zhang^#, Ying Li^#, Yashi Deng, Yilin Ou, Daocheng Ma, Dongdong Li, Weidong Xie^*, Zailiu Li^*
Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization of Subtropical Forest Plantation, Guangxi Key Laboratory of Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, 530004, China
* Corresponding Author: Weidong Xie. Email: ; Zailiu Li. Email:
# These authors contributed equally to this work

Phyton-International Journal of Experimental Botany https://doi.org/10.32604/phyton.2024.058083

Received 04 September 2024; Accepted 28 November 2024; Published online 19 December 2024

Abstract

To enhance the productivity of Carya illinoinensis cv. ‘Shaoxing’ and mitigate the loss of flowers and fruits, the effects of different concentrations of Piperonyl Butoxide (PBO) wettable powder (2, 5, and 10 g·L^–1) and Paclobutrazol (PP₃₃₃) (150, 300, and 450 mg·L^–1, based on active ingredients) on 6-year-old ‘Shaoxing’ plants were investigated with water sprayed as the control. The results showed that: (1) Treatment with 10 g·L^–1 PBO and 450 mg·L^–1 PP₃₃₃ significantly inhibited the excessive growth of ‘Shaoxing’ branches. Also, 10 g·L^–1 PBO exhibited the best diameter increment effect on fruiting branches, and 150 mg·L^–1 PP₃₃₃ exhibited the best diameter increment effect on vegetative branches. (2) The content of soluble sugar and soluble protein in leaves treated reached the highest level after treatment with 450 mg·L^–1 PP₃₃₃, while the content of starch sugar in leaves reached the highest level after treatment with 300 mg·L^–1 PP₃₃₃. The application of PBO and PP₃₃₃ mitigated the decline in N, P, K, and other nutrient levels observed in the leaves of ‘Shaoxing’. As the PBO and PP₃₃₃ concentrations increased, the nutrient elements in the leaves first increased and then decreased. Among them, 300 mg·L^–1 PP₃₃₃ treatment exhibited the best effect on increasing the content of N, P, and K in the leaves at the late stage of fruit development. (3) In terms of fruit setting rate and nutritional quality of ‘Shaoxing’ fruit, 5 g·L^–1 PBO treatment showed the most promising effect on improving fruit setting rate, 150 mg·L^–1 PP₃₃₃ exhibited the best effect on improving reducing sugar and decreasing tannin content in the kernel, 10 g·L^–1 PBO had the best effect on improving the crude fat content, and 2 g·L^–1 PBO had the best effect on improving the cellulose content in the kernel. (4) Principal component analysis showed that 450 mg·L^–1 PP₃₃₃ treatment had the most comprehensive regulatory effect on the growth and development of current-year branches, leaves, and fruits of ‘Shaoxing’. This study provided a theoretical basis and data reference for the growth and development of C. illinoinensis cv. ‘Shaoxing’ fruits from the perspective of the application of plant growth regulators.

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Keywords

Carya illinoinensis cv. ‘Shaoxing’; branch control; fruit quality; PBO; PP₃₃₃

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